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Aim: Macroecological studies that require habitat suitability data for many species often derive this information from expert opinion. However, expert- based informa-tion is inherently subjective and thus prone to errors. The increasing availability of GPS tracking data offers opportunities to evaluate and supplement expert- based in-formation with detailed empirical evidence. Here, we compared expert- based habitat suitability information from the International Union for Conservation of Nature (IUCN) with habitat suitability information derived from GPS-tracking data of 1,498 individu-als from 49 mammal species.Location: Worldwide.Time period: 1998–2021.Major taxa studied: Forty- nine terrestrial mammal species.Methods: Using GPS data, we estimated two measures of habitat suitability for each individual animal: proportional habitat use (proportion of GPS locations within a habi-tat type), and selection ratio (habitat use relative to its availability). For each individual we then evaluated whether the GPS- based habitat suitability measures were in agree-ment with the IUCN data. To that end, we calculated the probability that the ranking of empirical habitat suitability measures was in agreement with IUCN's classification into suitable, marginal and unsuitable habitat types.Results: IUCN habitat suitability data were in accordance with the GPS data (> 95% probability of agreement) for 33 out of 49 species based on proportional habitat use estimates and for 25 out of 49 species based on selection ratios. In addition, 37 and 34 species had a > 50% probability of agreement based on proportional habitat use and selection ratios, respectively.Main conclusions: We show how GPS-tracking data can be used to evaluate IUCN habitat suitability data. Our findings indicate that for the majority of species in-cluded in this study, it is appropriate to use IUCN habitat suitability data in macro-ecological studies. Furthermore, we show that GPS-tracking data can be used to identify and prioritize species and habitat types for re-evaluation of IUCN habitat suitability data. expert opinion, GPS, habitat suitability, habitat type, habitat use, IUCN, mammals, movement, selection ratio, telemetry

The parallel niche release hypothesis (PNR) indicates that reduced competition with dominant competitors results in greater density and niche breadth of subordinate competitors and which may support an adaptive advantage.We assessed support for the PNR by evaluating relationships between variation in niche breadth and intra- and interspecific density (an index of competition) of wolves (

Within optimality theory, an animal’s home range can be considered a fitness-driven attempt to obtain resources for survival and reproduction while minimizing costs. We assessed whether brown bears (Ursus arctos) in two island populations maximized resource patches within home ranges (Resource Dispersion Hypothesis [RDH]) or occupied only areas necessary to meet their biological requirements (Temporal Resource Variability Hypothesis [TRVH]) at annual and seasonal scales. We further examined how intrinsic factors (age, reproductive status) affected optimal choices. We found dynamic patterns of space use between populations, with support for RDH and TRVH at both scales. The RDH was likely supported seasonally as a result of bears maximizing space use to obtain a mix of nutritional resources for weight gain. While annually, support for RDH likely reflected changing abundances and distributions of foods within different timber stand classes. TRVH was supported at both scales, with bears minimizing space use when food resources were temporally concentrated. Range sizes and optimal strategies varied among sex and reproductive classes, with males occupying larger ranges, supporting mate seeking behavior and increased metabolic demands of larger body sizes. This work emphasizes the importance of scale when examining animal movement ecology, as optimal behavioral decisions are scale dependent.

Coexistence between humans and large carnivores may depend on carnivore adaptations to use developed landscapes while reducing human encounters. Roads are a widespread form of human development that carnivores may perceive as efficient travel routes or centers of human activity and associated risk. We compared the spatio-temporal responses of carnivores to human road use with high-resolution tracking of a large carnivore guild including American black bears (Ursus americanus), bobcats (Lynx rufus), coyotes (Canis latrans), and wolves (C. lupus) in Michigan, USA. All carnivores selected for roads when traveling at night but avoided roads during the day when human activity was greatest. Human activity explained 90% of temporal variation in road use across carnivore species, with a 3.2–3.7-fold increase in road use at times of low human activity which reduced carnivore activity overlap with humans by 27–42%. Similar but less pronounced activity changes occurred in areas up to 500 m from roads. Bears and wolves increased nocturnal activity with more roads in their home range, but not bobcats or coyotes. Despite increased diurnal activity in areas farther from roads, temporal overlap among carnivores was high regardless of road proximity. Our results suggest that spatio-temporal responses to roads were similar among carnivores and emphasized avoidance of humans over other carnivore species. Further, we provide support that carnivores can be diurnally active while avoiding humans by using areas farther from roads. However, carnivores which are primarily diurnal (e.g., black bears) or have a strong proclivity for using roads (e.g., wolves) likely require greater behavioral changes to avoid humans. Behavioral adaptations allowing multiple species to use and cross roads while avoiding humans are encouraging for human-carnivore coexistence.

The spatial scales at which animals make behavioral trade-offs is assumed to relate to the scales at which factors most limiting resources and increasing mortality risk occur. We used global positioning system collar locations of 29 reproductive-age female black bears (Ursus americanus Pallas, 1780) in three states to assess resource selection relative to bear population-specific density, an index of vegetation productivity, riparian corridors, or two road classes of and within home ranges during spring–summer of 2009–2013. Female resource selection was best explained by functional responses to vegetation productivity across nearly all populations and spatial scales, which appeared to be influenced by variation in bear density (i.e., intraspecific competition). Behavioral trade-offs were greatest at the landscape scale, but except for vegetation productivity, were consistent for populations across spatial scales. Females across populations selected locations nearer to tertiary roads, but females in Michigan and Mississippi selected main roads and avoided riparian corridors, whereas females in Missouri did the opposite, suggesting population-level trade-offs between resource (e.g., food) acquisition and mortality risks (e.g., vehicle collisions). Our study emphasizes that female bear population-level resource selection can be influenced by multiple spatially dependent factors, and that scale-dependent functional behavior should be identified for management of bears across their range.

Estimating spatial and temporal resource use and partitioning among carnivore species varies based on life history and is critical to understanding ecological relationships of sympatric carnivores and their prey. Temporal variation in food availability can have a substantial influence on distribution, foraging behavior, prey selection, and population dynamics of carnivores. We investigated shifts in space use of black bears (Ursus americanus), bobcats (Lynx rufus), coyotes (Canis latrans), and gray wolves (C. lupus) in response to seasonal availability of white‐tailed deer (Odocoileus virginianus) fawns in Michigan, USA, May–August 2009–2011. We used generalized linear mixed models to identify whether probabilistic fawn space use resulted in shifts in carnivore space use from deer pre‐parturition (PPP, 1 May–24 May) to fawn limited mobility (LMP, 25 May–30 June) and social mobility (SMP, 1 July–31 August) periods. We developed a rule‐based algorithm to identify “clusters” of carnivore GPS locations and investigated carnivore clusters to identify fawn predation sites. Carnivores shifted space use among periods, but responses varied among species regarding fawn space use. Black bears selected against areas with greater fawn use during LMP and selected areas with greater fawn use during SMP. We suggest black bear space use was unrelated to fawn space use and reflected availability of vegetative forage. Bobcats selected areas with greater fawn use during LMP and SMP. Coyotes were indifferent to areas where fawns occurred during LMP but selected against areas with greater fawn use during SMP, likely foraging on alternative prey. Coyotes were spatially constrained by wolves, selecting against areas with greater wolf use during LMP and SMP. Wolves selected against areas with greater fawn use during LMP and SMP and selected areas near habitat edges and areas containing livestock carcasses. Carnivore responses to fawn white‐tailed deer distribution and vulnerability were congruent with life history strategies, resulting in space use shifts in response to temporarily abundant resources. Carnivores did not overall rely predominantly on fawns, likely shifting their space use to maximize intake of other seasonal resources. These events provide additional insight into life history strategies among co‐occurring species and dynamics of multi‐species predator–prey systems.

Acquisition of resources can be costly and individuals are predicted to optimize foraging strategies to maximize net energy gain. Wolves (Canis lupus) would be expected to scavenge on subsidies from anthropogenic resources when these resources provide an energetic benefit over the capture of wild prey. We examined the effects of subsidies from anthropogenic resources in the form of livestock carcass dumps (LCDs) on wolf space use, activity, tortuosity, and diet in portions of North America’s northern hardwood/boreal ecosystem. We fitted 19 wolves with global positioning system collars during May–August of 2009–2011 and 2013–2015. Wolves with LCDs within their home ranges used areas adjacent to LCDs greater than non-LCD sites and had decreased home ranges and activity as compared to wolves without LCDs in their home ranges. Additionally, cattle comprised at least 22% of wolf diet from scavenging in areas with LCDs present as compared to no cattle in the diet of wolves without access to LCDs. Subsidies from anthropogenic resources in the form of LCDs can serve as attractants for wolves and alter wolf diet, activity, and ranging behavior. Apex predators may alter their behavior where subsidies from anthropogenic resources occur and management of these subsidies should be considered when attempting to reduce the impacts of humans on wolf behavior.

Infanticide occurs in a variety of animal species and infanticide risk has large implications for the evolution of behavior. Further, the sex hypothesis of sexual segregation predicts that for species in which infanticide occurs, females with dependent young will avoid males to reduce risk of sexually-selected infanticide. Infanticide risk-avoidance behavior has been studied primarily in social species, but also occurs in some solitary species. We used generalized linear mixed models to determine if space use and movements of female American black bears (Ursus americanus) during the breeding season were consistent with the sex hypothesis of sexual segregation in the Upper Peninsula of Michigan, USA. Space use and movements of female black bears (n = 16) were not consistent with avoidance behavior to reduce sexually-selected infanticide risk. Females with cubs occupied core areas (mean = 4.64 km2, standard error [SE] = 1.28) and home ranges (mean = 19.46 km2, SE = 5.10) of similar size to females without cubs (core area [mean = 4.11 km2, SE = 0.59]; home range [mean = 16.07 km2, SE = 2.26]), and those core areas and home ranges were not in areas with lesser relative probability of male use. Additionally, females with cubs did not reduce movements during times of day when male movements were greatest. As female bears do avoid potentially infanticidal males in populations with greater levels of infanticide, female black bears may exhibit variation in avoidance behavior based on the occurrence of infanticide.

Radiotelemetry and unmarked occupancy modeling have been used to estimate animal population growth, but have not been compared for ungulates. We compared white-tailed deer (Odocoileus virginianus) population growth estimates from radiomarked individuals and occupancy modeling of unmarked individuals and evaluated advantages and disadvantages of each method. Estimates of population growth were obtained using remote camera (N = 54/year) detection/non-detection occupancy surveys of unmarked deer and from survival and recruitment data of radiomarked adult females (N = 87) and neonate fawns (N = 127) in a predominantly forested region of the Upper Peninsula of Michigan, USA, 2009–2011. We hypothesized that occupancy models and radiotelemetry data would have similar population growth trends because both methods sampled the same temporally closed population. Percent changes in camera trap data generally reflected finite population growth (λ) of radiomarked deer which increased (λ = 1.10 ± 0.01) from 2009 to 2010, but decreased (λ = 0.87 ± 0.02) from 2010 to 2011. Also, unmarked adult female abundance and fawn:adult female ratios generally reflected trends in radiomarked deer survival and recruitment. Royle–Nichols occupancy model abundance estimates had wide confidence intervals, which may preclude using this method from accurately estimating deer population growth. Radiotelemetry provided more precise population growth estimates, while allowing collection of vital rates and location data. However, the Royle–Nichols occupancy model may be preferred to radiotelemetry because it reflected yearly variation in population growth with reduced labor and no invasive marking. Researchers should consider the objectives and logistics of their study when choosing a specific method.

The role of predation in ecological systems has received considerable attention in scientific literature and is one of the most important, yet least understood aspects of carnivore ecology. Knowledge of factors that improve our ability to detect predation events using animal telemetry data could be used to develop strategies to reduce time and resources required to obtain reliable kill estimates. Using Global Positioning System telemetry-collars, we investigated 246 bobcat Lynx rufus location clusters to identify white-tailed deer Odocoileus virginianus kill sites in the Upper Peninsula of Michigan, USA, during May-August, 2009-2011. We documented kills of white-tailed deer at 42 location clusters. We used logistic regression and Akaike Information Criterion for small samples to identify factors (i.e. number of locations in cluster, time from cluster formation to investigation, time of day and land cover) that may influence bobcat behaviour and our ability to detect white-tailed deer kill sites. Clusters ...

Ketamine and xylazine are an effective chemical combination for white-tailed deer (Odocoileus virginianus) immobilization, but the effects of body condition on ketamine-xylazine efficacy have not been examined. We assessed the influence of ketamine dosage, xylazine dosage, body condition, age class, and injection site on successful adult female deer chemical immobilization. From January to March 2009-2011, we captured 87 deer (age � 1.5 yr) in Clover traps and immobilized them using ketamine-xylazine ratios of 400 mg (n ¼ 58) or 300 mg (n ¼ 29) of ketamine to 100 mg of xylazine. Mean deer body mass was 67.8 kg (SD ¼ 12.3, range ¼ 43.0-93.0). We considered immobilization successful if deer induction was achieved � 15 minutes from first ketamine-xylazine injection. Seventy-five percent of injected deer (81% with 400:100 mg ketamine:xylazine; 62% with 300:100 mg ketamine:xylazine) achieved successful induction. We recorded deer heart rate, respiration rate and rectal temperature at 0 minutes, 10 minutes, and 20 minutes post-induction. Comparison of 7 generalized linear models indicated that the probability of successful induction increased by about 6.7% with every 1.0 mg/kg increase in ketamine dosage and by about 0.7% with every 1-unit decrease in body-condition index. The remaining parameters did not influence the success of deer induction. Deer heart rate, respiration rate, and rectal temperature decreased over time post- induction, with >95% within reported ranges for ketamine-xylazine immobilization. We suggest that deer weighing � 93.0 kg be injected with 5.8 mg/kg ketamine and 1.6 mg/kg xylazine to produce satisfactory induction when using similar capture methods during winter. 2012 The Wildlife Society.

Information regarding American black bear (Ursus americanus) mortality caused by disease is limited. Pneumonia is a common respiratory disease that affects many species of wildlife and can result in death. In February 2011, we investigated the death of a yearling male black bear and determined cause of death to be aspiration pneumonia. We found sections of lung were diffusely congested and edematous. A bacterial culture of lung tissue revealed numerous colonies of Klebsiella spp., Alcaligenes faecalis, Aeromonas spp., Corynebacterium spp., and Streptococcus spp. The mixed bacterial colonization of the lungs associated with minimal inflammation is consistent with terminal aspiration of gastrointestinal contents resulting in aspiration pneumonia. Documentation of aspiration pneumonia in black bears can be useful for future researchers interested in the effects of disease on bears.

Assessing ungulate reproduction is important to biologists for managing populations and predicting trends. We compared efficacy of trans-abdominal ultrasound and pregnancy-specific protein B (PSPB) white-tailed deer (Odocoileus virginianus) pregnancy estimates, respectively, from January to mid-April 2009–2011 in the south-central Upper Peninsula of Michigan, USA. We observed a strong agreement (K = 0.68, SE = 0.13, 95% CI = 0.42–0.94) of PSPB and ultrasound in categorizing pregnant and nonpregnant deer. Five deer were determined to be pregnant by ultrasound but not by PSPB and 6 females were judged to be nonpregnant using either method. Total cost for PSPB testing of 101 deer was US$2,220, whereas ultrasound equipment cost US$14,150. Trans-abdominal ultrasound and PSPB provided accurate detection of pregnancy in live white-tailed deer. We recommend PSPB for studies testing comparatively small numbers (up to several hundred) of deer. However, we recommend ultrasonography if real-time pregnancy determination is needed (e.g., vaginal implant transmitter use), particularly for large numbers (i.e., several hundred to thousands) of deer. © 2012 The Wildlife Society.

American black bears (Ursus americanus) are opportunistic omnivores and can be proficient predators of neonate ungulates, but predation of adult ungulates is rare. In November 2009 we investigated a probable black bear predation of a radiocollared, adult (7.5 years old) female white-tailed deer (Odocoileus virginianus) in a densely vegetated, lowland conifer forest in the Upper Peninsula of Michigan, USA. The deer carcass was 80% buried with puncture wounds and lacerations on the back and hindquarters. The hide was everted, the intestines and stomach partially eaten, the mammary glands were punctured, and the skeleton remained articulated. All woody vegetation

Haliaeetus leucocephalus (Bald Eagle) is an adaptable predatory bird that commonly captures live prey, but regularly scavenges. Large mammalian prey (e.g., Odocoileus virginianus [White-tailed Deer]) have been observed in Bald Eagle diets, but were considered scavenged. To our knowledge, Bald Eagle predation of a live ungulate has only been reported once, and occurred in Menominee County, MI. In June 2009, we captured and radiocollared a female White-tailed Deer fawn (2.7 kg) in the south-central Upper Peninsula of Michigan. The fawn was last radiolocated alive 8 h after release in a short-height (20–30 cm) grassland field along a river approximately 570 m from an eagle nest. Estimated time of mortality of the fawn was 10 h post release. Approximately 27 h post release, 2 legs, >50% fawn hide, and the radiocollar were present in the nest along with 2 eagle nestlings (estimated age 9–10 wks). We believe this was a possible predation event based on the 8-h period between fawn relocations, fawn move...

Female ungulate reproductive success is dependent on the survival of their young, and affected by maternal resource selection, predator avoidance, and nutritional condition. However, potential hierarchical effects of these factors on reproductive success are largely unknown, especially in multi-predator landscapes. We expanded on previous research of neonatal white-tailed deer (Odocoileus virginianus) daily survival within home ranges to assess if resource use, integrated risk of 4 mammalian predators, maternal nutrition, winter severity, hiding cover, or interactions among these variables best explained landscape scale variation in daily or seasonal survival during the post-partum period. We hypothesized that reproductive success would be limited greater by predation risk at coarser spatiotemporal scales, but habitat use at finer scales. An additive model of daily non-ideal resource use and maternal nutrition explained the most (69%) variation in survival; though 65% of this variation was related to maternal nutrition. Strong support of maternal nutrition across spatiotemporal scales did not fully support our hypothesis, but suggested reproductive success was related to dam behaviors directed at increasing nutritional condition. These behaviors were especially important following severe winters, when dams produced smaller fawns with less probability of survival. To increase nutritional condition and decrease wolf (Canis lupus) predation risk, dams appeared to place fawns in isolated deciduous forest patches near roads. However, this resource selection represented non-ideal resources for fawns, which had greater predation risk that led to additive mortalities beyond those related to resources alone. Although the reproductive strategy of dams resulted in greater predation of fawns from alternative predators, it likely improved the life-long reproductive success of dams, as many were late-aged (>10 years old) and could have produced multiple litters of fawns. Our study emphasizes understanding the scale-dependent hierarchy of factors limiting reproductive success is essential to providing reliable knowledge for ungulate management.

The trade-off between predator avoidance and foraging is a key decision making factor that shapes an organism's adaptive behaviour and movement patterns. Human hunters act as top predators to influence the behaviour of free-ranging mammals, including large carnivorous species such as black bears (Ursus americanus). Analysing the effects of hunting on animal behavioural patterns is essential for understanding the extent to which animals detect and respond to human-induced disturbances. To this end, we assessed whether black bear movement behaviour changed with varying risk from spatially and temporally heterogeneous human predation. Levels of risk were categorized as either low (disturbance from dog training; n=19 bears) or high (disturbance from hunting activities; n=11 bears). Road types were either paved (risk due to vehicles) or non-paved (risk due to hunters) and were used as proxies for hunting effort and amount of disturbance. We began by testing the null hypothesis that bears' distribution before the onset of human disturbance is spatially random. Next, to test temporal movement adjustment between the low and high risk levels, we measured the distance to the nearest road and the road crossing frequency using mixed effects models with risk level, time of day and sex as predictor variables. As disturbance near non-paved roads increased due to the start of the hunting activity, the mean distances of bears to non-paved roads increased while the mean distances of bears to paved roads decreased, despite the continual risk of vehicle collision. These behavioural responses were observed during day and night, with the frequency of crossing paved roads at night five times greater than in daytime during the hunting season. Our findings demonstrate that black bears are able to detect risky places and adjust their spatial movements accordingly. More specifically, bears can perceive changes in the level of risk from human hunting activities on a fine temporal scale.

Growth of ungulate populations is typically most sensitive to survival of neonates, which in turn is influenced by maternal nutritional condition and trade-offs in resource selection and avoidance of predators. We assessed whether resource use, multi-predator risk, maternal nutritional effects, hiding cover, or interactions among these variables best explained variation in daily survival of free-ranging neonatal white-tailed deer (Odocoileus virginianus) during their post-partum period (14 May–31 Aug) in Michigan, USA. We used Cox proportional hazards mixed-effects models to assess survival related to covariates of resource use, composite predation risk of 4 mammalian predators, fawn body mass at birth, winter weather, and vegetation growth phenology. Predation, particularly from coyotes (Canis latrans), was the leading cause of mortality; however, an additive model of non-ideal resource use and maternal nutritional effects explained 71% of the variation in survival. This relationship suggested that dams selected areas where fawns had poor resources, while greater predation in these areas led to additive mortalities beyond those related to resource use alone. Also, maternal nutritional effects suggested that severe winters resulted in dams producing smaller fawns, which decreased their likelihood of survival. Fawn resource use appeared to reflect dam avoidance of lowland forests with poor forage and greater use by wolves (C. lupus), their primary predator. While this strategy led to greater fawn mortality, particularly by coyotes, it likely promoted the life-long reproductive success of dams because many reached late-age (>10 years old) and could have produced multiple generations of fawns. Studies often link resource selection and survival of ungulates, but our results suggested that multiple factors can mediate that relationship, including multi-predator risk. We emphasize the importance of identifying interactions among biological and environmental factors when assessing survival of ungulates.